Circulating nucleic acids, encapsulated within small extracellular vesicles (EVs), provide a remote cellular snapshot of biomarkers derived from diseased tissues, however selective isolation is critical. Current laboratory-based purification techniques rely on the physical properties of small-EVs rather than their inherited cellular fingerprints. We established a highly-selective purification assay, termed EV-CATCHER, initially designed for high-throughput analysis of low-abundance small-RNA cargos by next-generation sequencing. We demonstrated its selectivity by specifically isolating and sequencing small-RNAs from mouse small-EVs spiked into human plasma. Western blotting, nanoparticle tracking, and transmission electron microscopy were used to validate and quantify the capture and release of intact small-EVs. As proof-of-principle for sensitive detection of circulating miRNAs, we compared small-RNA sequencing data from a subset of small-EVs serum-purified with EV-CATCHER to data from whole serum, using samples from a small cohort of recently hospitalized Covid-19 patients. We identified and validated, only in small-EVs, hsa-miR-146a and hsa-miR-126-3p to be significantly downregulated with disease severity. Separately, using convalescent sera from recovered Covid-19 patients with high anti-spike IgG titers, we confirmed the neutralizing properties, against SARS-CoV-2 in vitro, of a subset of small-EVs serum-purified by EV-CATCHER, as initially observed with ultracentrifuged small-EVs. Altogether our data highlight the sensitivity and versatility of EV-CATCHER.The clinical manifestations of COVID-19 vary broadly, ranging from asymptomatic infection to acute respiratory failure and death. But the predictive biomarkers for characterizing the variability are still lacking. Since emerging evidence indicates that extracellular vesicles (EVs) and extracellular RNAs (exRNAs) are functionally involved in a number of pathological processes, we hypothesize that these extracellular components may be key determinants and/or predictors of COVID-19 severity. To test our hypothesis, we collected serum samples from 31 patients with mild COVID-19 symptoms at the time of their admission for discovery cohort. After symptomatic treatment without corticosteroids, 9 of the 31 patients developed severe/critical COVID-19 symptoms. We analyzed EV protein and exRNA profiles to look for correlations between these profiles and COVID-19 severity. Strikingly, we identified three distinct groups of markers (antiviral response-related EV proteins, coagulation-related markers, and liver damage-related exRNAs) with the potential to serve as early predictive biomarkers for COVID-19 severity. As the best predictive marker, EV COPB2 protein, a subunit of the Golgi coatomer complex, exhibited significantly higher abundance in patients remained mild than developed severe/critical COVID-19 and healthy controls in discovery cohort (AUC 1.00 (95% CI 1.00-1.00)). The validation set included 40 COVID-19 patients and 39 healthy controls, and showed exactly the same trend between the three groups with excellent predictive value (AUC 0.85 (95% CI 0.73-0.97)). These findings highlight the potential of EV COPB2 expression for patient stratification and for making early clinical decisions about strategies for COVID-19 therapy.Adamantinoma is a low-grade malignant bone tumor with metastatic potential in the range of 15-20%, commonly affecting mid-diaphyseal tibial region and jaw. Numerous cases of adamantinoma affecting the appendicular skeleton have been reported but only three in the pelvis till date. We present the case of a 24-year-old male, who was initially reported as fibrous dysplasia for a lesion in pelvis. On review, a cellular tumor was noted, including areas resembling fibrous dysplasia, along with cords and nests of polygonal cells, which displayed positive immunoexpression with cytokeratin and p40. Subsequently, he underwent wide local resection (internal hemipelvectomy), along with mesh pseudoarthrosis was done. Diagnosis of adamantinoma was further confirmed, with clear resection margins. Currently, the patient is on a regular clinical and radiological follow-up. Careful assessment of key histomorphologic features, coupled with immunohistochemical stains and clinico-radiological correlation, is helpful in identifying this uncommon tumor at a rather rare site.A 15 years old boy presented with an atypical osteoid osteoma (OO) in distal femur. He underwent radiofrequency ablation (RFA) elsewhere. He presented to our centre a year later with persisting pain. click here MR scan showed incomplete ablation of the nidus as there was only a single pass of the RF probe for a 14 mm long linear lesion. We also found penumbra sign and wall enhancement on contrast MRI suggestive of a Brodie's abscess (BA). Under CT guidance the OO was drilled and BA was saucerised. Following this he was treated with culture sensitive antibiotics and his symptoms resolved. BA and OO are common differential diagnoses. RFA of OO leading to BA has not been reported in literature. Atypical linear OO requires multiple probe placements to ablate the long nidus. Diligent care should be taken to avoid intraoperative contamination in CT room which could lead to infection. Soft tissue defects due to trauma with crush injuries and post-tumor excision are large in size. Free anterolateral flap provides a stable and durable coverage of soft tissue defects and leads to good functional outcomes. Between January 2017 and January 2019, eight males and six female patients with soft tissue defects were operated upon using a free anterolateral thigh flaps. The defects in ten patients were due to post-tumor extirpation and in four patients due to wound breakdown following post-tumor extirpation. The average flap dimension was 14cm × 12cm. The mean follow-up was 11months (4-28months). All the flaps survived well except in one patient who with an upper limb defect, had flap necrosis owing to which patient needed to undergo abdominal flap coverage. Two patients with sarcoma developed local recurrence and had to undergo above‑knee amputation. The method of reconstruction depends on the size of defect and area to be covered and need of post-surgery mobilization and need for radiotherapy.